Calibrator No 10

Calibrator Crystal No 10

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General Description

The Calibrator, Crystal No10 is primarily designed for the purpose of setting up Wireless set No 62 accurately on the required spot frequency.

The calibrator functions as a CW wavemeter with continuous coverage of a nominal frequency band of 1.5 - 10.0 Mc/s.

The calibrator power supplies are obtained from the socket engraved XTAL CAL on the Wireless Set 62.

Technical Data

The following facilities are available:

1. Selector switch to 500kc/s position.
A crystal controlled oscillator provides fixed frequency signals of 500kc/s to well beyond 10mc/s.

2. Selector switch in DIAL position.
In addition to the 500kc oscillator, a second and variable oscillator (250-500kc) is brought into circuit. This enables all frequencies between 500kc and 10mc to be produced - these frequencies are indicated on the dial on the front panel.

For identification purposes, the calibrator signal is modulated at about 1 cycle per second by means of a neon tube.

The output from the calibrator is taken from the terminal engraved AERIAL on the front panel.

Power Supply (ex WS62)
         LT 12v dc at 300ma - series heaters - 1.4v valve heaters.
         HT 300v dc at 15ma


Useful output exists on the 2 metre band.

The wire colours in the power lead do not follow convention!!

Beware of selecting the wrong output signal as there are an incredible number of unwanted beats.

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© Ian O'Toole, 2009. Page created: 28/04/03 Last updated: 4/12/2009